V1.3: Custom Helpers
In the overview section, we introduced the design for helpers. They are modules that enrich views’ behaviors. Because they are just Ruby modules, we can create our own helpers.
Imagine we need (for some reason) a helper that shuffles the characters of a string and we want it to be available in our views.
First, let’s define a
Web::Helpers::Shuffler module, and put it within a new
# app/web/helpers/shuffler.rb module Web module Helpers module Shuffler private SEPARATOR = ''.freeze def shuffle(string) string .encode(Encoding::UTF_8, invalid: :replace) .split(SEPARATOR).shuffle.join end end end end
There is NO coupling between the file name and the name of the module. We can define this code where and how we want.
Now let’s make this helper available to use by editing our app’s
application.rb. First, add that new
helpers directory to the load paths of the application so it can be eagerly loaded. Second, include the
Web::Helpers::Shuffler module in all the views. See the Views: Share Code section for low-level details.
# apps/web/application.rb module Web class Application < Hanami::Application configure do # ... load_paths << [ 'helpers', 'controllers', 'views' ] # ... view.prepare do include Hanami::Helpers include Web::Helpers::Shuffler end end end end
Please note that our custom helper will work even if we remove the
include Hanami::Helpers line, because it’s just Ruby.